Utility of preoperative meningioma consistency measurement with magnetic resonance elastography (MRE): a review.

Meningioma consistency is a critical factor that influences preoperative planning for surgical resection. Recent studies have investigated the utility of preoperative magnetic resonance elastography (MRE) in predicting meningioma consistency. However, it is unclear whether existing methods are optimal for application to clinical practice. The results and conclusions of these studies are limited by their imaging acquisition methods, such as the use of a single MRE frequency and the use of shear modulus as the final measurement variable, rather than its storage and loss modulus components. In addition, existing studies do not account for the effects of cranial anatomy, which have been shown to significantly distort the MRE signal. Given the interaction of meningiomas with these anatomic structures and the lack of supporting evidence with more accurate imaging parameters, MRE may not yet be reliable for use in clinical practice.

Deep brain stimulation of the ventralis intermedius nucleus for the treatment of essential tremor.

A 59-year-old woman with a 30-year history of essential tremor refractory to medical therapy underwent staged deep brain stimulation of the ventralis intermedius nucleus of the thalamus (VIM). Left-sided lead placement was performed first. Once in the operating room, microelectrode recording (MER) was performed to confirm the appropriate trajectory and identify the VIM border with the ventralis caudalis nucleus. MER was repeated after repositioning 2 mm anteriorly to reduce the likelihood of stimulation-induced paresthesias. Physical examination prior to permanent lead placement demonstrated micro-lesion effect, suggesting optimal trajectory. After implantation of the permanent lead, physical examination showed excellent results. The video can be found here: https://youtu.be/nn3KRdmRCZ4 .

A step-down unit transfer protocol for low-risk aneurysmal subarachnoid hemorrhage.

OBJECTIVE Patients who have experienced subarachnoid hemorrhage (SAH) often receive care in the setting of the ICU. However, SAH patients may not all require extended ICU admission. The authors established a protocol on January 1, 2015, to transfer select, low-risk patients to a step-down unit (SDU) to streamline care for SAH patients. This study describes the results of the implemented protocol. METHODS In this retrospective chart review, patients presenting with SAH between January 2011 and September 2016 were reviewed for inclusion. The control group consisted of patients admitted prior to establishment of the SDU transfer protocol, while the intervention group consisted of patients admitted afterward. RESULTS Of the patients in the intervention group, 79.2% (57/72) were transferred to the SDU during their admission. Of these transferred patients, 29.8% (17/57) required return to the neurosurgical ICU (NSICU). There were no instances of morbidity or mortality directly related to care in the SDU. Patients in the intervention group had a mean reduced NSICU length of stay, by 1.95 days, which trended toward significance, and a longer average hospitalization, by 2.7 days, which also trended toward significance. In-hospital mortality and 90-day readmission rate were not statistically different between the groups. In addition, early transfer timing prior to 7 days was associated with neither a higher return rate to the NSICU nor higher 90-day readmission rate. CONCLUSIONS In this retrospective study, the authors demonstrated that the transfer protocol was safe, feasible, and effective in reducing the ICU length of stay and was independent of transfer timing. Confirmation of these results is needed in a large, multicenter study.

Novel and emerging technologies for endovascular thrombectomy.

Endovascular thrombectomy device improvements in recent years have served a pivotal role in improving the success and safety of the thrombectomy procedure. As the intervention gains widespread use, developers have focused on maximizing the reperfusion rates and reducing procedural complications associated with these devices. This has led to a boom in device development. This review will cover novel and emerging technologies developed for endovascular thrombectomy.

Minipterional craniotomy for resection of epileptogenic cavernous malformation.

Epilepsy is a common symptom of pediatric cavernous malformations. In medically refractory patients, surgery can achieve high seizure freedom rates with low morbidity. This video depicts the use of a minipterional craniotomy and transsulcal resection of a frontal opercular cavernous malformation in a 13-year-old female with medically intractable epilepsy. At 1-year follow-up, she was evaluated as Engel class I with a significant improvement in her quality of life. Principles of cavernous malformation resection for the treatment of epilepsy are also reviewed. The video can be found here: https://stream.cadmore.media/r10.3171/2024.4.FOCVID2441.

Endoscopic endonasal approach for MRI-Negative Cushing's microadenoma.

A 54-year-old male with a history of diabetes mellitus type 2 for 12 years and hypertension was seen in the clinic due to poorly controlled diabetes. Inferior petrosal sinus sampling (IPSS) confirmed Cushing's disease with primary adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma on the right. However, 3T and subsequent 7T MRI showed no visible tumor. An endoscopic transsphenoidal approach was selected to explore the pituitary gland and resect the presumed microadenoma. Tumor was identified in the lateral recess along the right medial cavernous sinus wall and gross-total resection (GTR) was performed. The normal pituitary gland was preserved, and the patient went into remission. The video can be found here: https://stream.cadmore.media/r10.3171/2023.4.FOCVID2324.

Preexisting Ventricular Shunts Are Associated with Failed Evacuation of Acute Subdural Hematomas: Single-Institution Case Series of Complications and Management Strategies.

BACKGROUND: The effect of ventricular shunts on radiographic outcomes after evacuation of acute subdural hematomas (aSDHs) has not yet been established. We studied a series of patients who had undergone craniotomy for aSDH, exploring a possible relationship between the occurrence of a postoperative extra-axial collection (EAC) and the presence of a ventricular shunt. METHODS: We reviewed all craniotomies for convexity aSDH performed between July 2015 and June 2020. The medical record review included perioperative coagulation studies, platelet counts, and antiplatelet and anticoagulation agent use. Univariate and multivariate analyses were conducted to identify the factors associated with postoperative EACs and reevacuation. RESULTS: A total of 58 patients had undergone craniotomy for aSDHs, including 9 with ventricular shunts. The median age was 67 years (interquartile range, 54-78 years), and 40% of the patients were women. Of the 58 patients, 16 were taking antiplatelet agents, and 6 were taking anticoagulation agents. Ten patients had developed perioperative thrombocytopenia (platelet count, <100,000/µL). Twelve patients had perioperative coagulopathy (international normalized ratio, ≥1.5). A postoperative EAC >10 mm occurred in 17 patients (29.3%). Eight patients (13.8%) had undergone reevacuation. The presence of a shunt and an increasing preoperative aSDH size were independently associated with an EAC >10 mm (P = 0.013 and P = 0.003, respectively). Only the presence of a shunt predicted for the need for reevacuation (P = 0.001). The shunts were explanted (n = 3) or valves were adjusted (n = 3) in all but 3 cases. CONCLUSIONS: We found that a lack of brain reexpansion after aSDH evacuation worsens radiographic outcomes and was more common in patients with shunts. Increasing shunt valve resistance might help prevent the formation of large EACs after aSDH evacuation.

Definition and time course of pericavity edema after minimally invasive endoscopic intracerebral hemorrhage evacuation.

BACKGROUND: Perihematomal edema (PHE) volume correlates with intracerebral hemorrhage (ICH) volume and is associated with functional outcome. Minimally invasive surgery (MIS) for ICH decreases clot burden and PHE. MIS may therefore alter the time course of PHE, mitigating a critical source of secondary injury. OBJECTIVE: To describe a new method for the quantitative measurement of cerebral edema surrounding the evacuated hematoma cavity, termed pericavity edema (PCE), and obtain details of its time course following MIS for ICH. METHODS: The study included 48 consecutive patients presenting with ICH who underwent MIS evacuation. Preoperative and postoperative CT scans were assessed by two independent raters. Hematoma, edema, cavity, and pneumocephalus volumes were calculated using semi-automatic, threshold-guided volume segmentation software (AnalyzePro). Follow-up CT scans at variable delayed time points were available for 36 patients and were used to describe the time course of PCE. RESULTS: Mean preoperative, postoperative, and delayed PCE were 21.0 mL (SD 15.5), 18.6 mL (SD 11.4), and 18.4 mL (SD 15.5), respectively. The percentage of ICH evacuated correlated significantly with a decrease in postoperative PCE (r=-0.46, p<0.01). Linear regression analysis revealed a significant relation between preoperative hematoma volume and both postoperative PCE (p<0.001) and postoperative relative PCE (p<0.001). The mean peak PCE was 26.4 mL (SD 15.6) and occurred at 6.5 days (SD 4.8) post-ictus. The 2-week postoperative time course of relative PCE did not fluctuate, suggesting stability in edema during the perioperative period surrounding evacuation and up to 2 weeks after the initial bleed. CONCLUSIONS: We present a detailed and accurate method for measuring PCE volume with semi-automatic, threshold-guided segmentation software in the postoperative patient with ICH. Decrease in PCE after MIS evacuation correlated with evacuation percentage, and relative PCE remained stable after minimally invasive endoscopic ICH evacuation.

Minimally Invasive Endoscopic Intracerebral Hemorrhage Evacuation.

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and poor functional outcomes, largely because there are no evidence-based treatment options for this devastating disease process. In the past decade, a number of minimally invasive surgeries have emerged to address this issue, one of which is endoscopic evacuation. Stereotactic ICH Underwater Blood Aspiration (SCUBA) is a novel endoscopic evacuation technique performed in a fluid-filled cavity using an aspiration system to provide an additional degree of freedom during the procedure. The SCUBA procedure utilizes a suction device, endoscope, and sheath and is divided into two phases. The first phase involves maximal aspiration and minimal irrigation to decrease clot burden. The second phase involves increasing irrigation for visibility, decreasing aspiration strength for targeted aspiration without disturbing the cavity wall, and cauterizing any bleeding vessels. Using the endoscope and aspiration wand, this technique aims to maximize hematoma evacuation while minimizing collateral damage to the surrounding brain. Advantages of the SCUBA technique include the use of a low-profile endoscopic sheath minimizing brain disruption and improved visualization with a fluid-filled cavity rather than an air-filled one.

Frailty Is Associated with In-Hospital Morbidity and Nonroutine Disposition in Brain Tumor Patients Undergoing Craniotomy.

OBJECTIVE: Frailty is associated with postoperative morbidity in multiple surgical disciplines. We evaluated the association between frailty and early postoperative outcomes for brain tumor patients using a national database. METHODS: We reviewed the Nationwide Readmissions Database from 2010 to 2014. International Classification of Diseases, ninth revision, codes were used to identify benign and malignant brain tumors treated with surgical resection. Pituitary tumors were excluded. Frailty was assessed using the Johns Hopkins Adjusted Clinical Groups frailty indicator tool. Multivariable exact logistic regression was used to conduct analyses assessing the association between frailty and the outcome variables. Statistical significance was defined as P < 0.001. RESULTS: The criteria for frailty were met for 7209 of 87,835 patients (8.2%). After adjustment for patient and hospital factors, frailty was independently associated with in-hospital surgical complications (odds ratio [OR], 1.48; 95% confidence interval [CI] 1.37-1.59; P < 0.0001), mental status changes (OR, 1.9; 95% CI, 1.72-2.09; P < 0.0001), and pulmonary insufficiency (OR, 1.75; 95% CI, 1.55-1.96; P < 0.0001). Frailty was associated with an increased length of stay (incident rate ratio, 1.92; 95% CI, 1.87-1.98; P < 0.0001) and nonroutine disposition (OR, 1.84; 95% CI, 1.72-1.97; P < 0.0001). In-hospital mortality was greater for frail patients (2.2% vs. 1.4%; P < 0.0001), but the difference did not achieve significance on multivariate analysis. Frail patients were not more likely to be readmitted. CONCLUSION: Frailty is associated with in-hospital complications and nonroutine disposition after craniotomy for benign and malignant brain tumors. Additional work is needed to identify prehabilitation or in-hospital strategies to improve the care and outcomes of these at-risk patients.

Functional Outcome After Minimally Invasive Endoscopic Evacuation of Thalamic Intracerebral Hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is the most devastating form of stroke, with thalamic hemorrhages carrying the worst outcomes. Minimally invasive (MIS) endoscopic ICH evacuation is a promising new therapy for the condition. However, it remains unclear whether therapy success is location dependent. Here we present long-term functional outcomes after MIS evacuation of spontaneous thalamic hemorrhages. METHODS: Patients presenting to a single urban health system with spontaneous ICH were triaged to a central hospital for management of ICH. Operative criteria for MIS evacuation included hemorrhage volume ≥15 mL, age ≥18, National Institutes of Health Stroke Scale ≥6, and baseline modified Rankin Score (mRS) ≤3. Demographic, radiographic, and clinical data were collected prospectively, and descriptive statistics were performed retrospectively. Functional outcomes were assessed using 6-month mRS scores. RESULTS: Endoscopic ICH evacuation was performed on 21 patients. Eleven patients had hemorrhage confined to the thalamus, whereas 10 patients had hemorrhages in the thalamus and surrounding structures. Eighteen patients (85.7%) had intraventricular extension. The average preoperative volume was 39.8 mL (standard deviation [SD]: 31.5 mL) and postoperative volume was 3.8 mL (SD: 6.1 mL), resulting in an average evacuation rate of 91.4% (SD: 11.1%). One month after hemorrhage, 2 patients (9.5%) had expired and all other patients remained functionally dependent (90.5%). At 6-month follow-up, 4 patients (19.0%) had improved to a favorable outcome (mRS ≤ 3). CONCLUSION: Among patients with ICH undergoing medical management, those with thalamic hemorrhages have especially poor outcomes. This study suggests that MIS evacuation can be safely performed in a thalamic population. It also presents long-term functional outcomes that can aid in planning randomization schemes or subgroup analyses in future MIS evacuation clinical trials.

Ventricular Catheter Tract Hemorrhage as a Risk Factor for Ventriculostomy-Related Infection.

BACKGROUND: Ventriculostomy-related infection (VRI) is a feared complication of external ventricular drain (EVD) placement. Although many contributing factors to VRI have been examined, little is known whether there is an association between ventriculostomy-related catheter tract hemorrhage (VCTH) and VRI. OBJECTIVE: To evaluate risk factors for VRI and assess possible correlations with VCTH. METHODS: We performed a retrospective analysis of patients with EVD placement in a neurocritical care unit between 2011 and 2015. VRI was defined as clinical signs of infection with a positive cerebrospinal fluid gram stain and isolation of cerebrospinal fluid culture. VCTH was diagnosed by computed tomography immediately after EVD insertion. RESULTS: A total of 247 patients with EVD were identified during the 5-yr study period. An association between VCTH and gram-negative VRI was identified (P = .02). Ten percent (25 of 247 patients) developed a VRI, and 7% (18 of 247 patients) had a VCTH. Of the 25 patients with VRI, 20% (n = 5) had a VCTH, compared to 6% (n = 13) of 222 patients who had an EVD placed but did not develop VRI. There were no significant differences in demographic and clinical factors except for multiple EVD insertions (P < .00001), EVD duration (P < .001), and hospital length of stay (P < .001). CONCLUSION: VCTH is a potentially significant risk factor for VRI. Further analysis will be needed to confirm the strength of this association, and to delineate the possible mechanisms by which tract hemorrhage may serve as a nidus for bacterial penetration into the central nervous system.

A Compendium of Modern Minimally Invasive Intracerebral Hemorrhage Evacuation Techniques.

BACKGROUND: Minimally invasive intracerebral hemorrhage (ICH) evacuation has gained popularity with success in early-phase clinical trials. This procedure, however, is performed in very different ways around the world. OBJECTIVE: To provide a technical description of these strategies that facilitates comparison and aids decisions in which surgery to perform, and to inform further improvements in minimally invasive ICH evacuation. METHODS: Major authors of clinical trials evaluating each of the main techniques were contacted and asked to supply a case example and technical description of their respective surgeries. RESULTS: Five major techniques are presented including stereotactic thrombolysis, craniopuncture, endoscopic, endoscope-assisted, and endoport-mediated. Techniques differ in numerous ways including the size of the cranial access, the size of the access corridor through the brain to the hematoma, and the evacuation strategy. Regarding cranial access, a burr hole is created in stereotactic thrombolysis and craniopuncture, a small craniectomy in endoscopic, and a small craniotomy in the other 2. Access corridors through the parenchyma range from 3 mm in craniopuncture to 13.5 mm in the endoport-mediated evacuation. Regarding evacuation strategies, stereotactic thrombolysis and craniopuncture rely on passive drainage from a catheter placed during surgery that remains in place for multiple days, while the other 3 techniques rely on active evacuation with suction and bipolar cautery. CONCLUSION: Future comparative clinical trials may identify the advantageous components of each strategy and contribute to improved outcomes in this patient population.

Advanced Techniques for Endoscopic Intracerebral Hemorrhage Evacuation: A Technical Report With Case Examples.

BACKGROUND: Multiple surgical techniques to perform minimally invasive intracerebral hemorrhage (ICH) evacuation are currently under investigation. The use of an adjunctive aspiration device permits controlled suction through an endoscope, minimizing collateral damage from the access tract. As with increased experience with any new procedure, performance of endoscopic minimally invasive ICH evacuation requires development of a unique set of operative tenets and techniques. OBJECTIVE: To describe operative nuances of endoscopic minimally invasive ICH evacuation developed at a single center over an experience of 80 procedures. METHODS: Endoscopic minimally invasive ICH evacuation was performed on 79 consecutive eligible patients who presented a single Health System between March 2016 and May 2018. We summarize 4 core operative tenets and 4 main techniques used in 80 procedures. RESULTS: A total of 80 endoscopic minimally invasive ICH evacuations were performed utilizing the described surgical techniques. The average preoperative and postoperative volumes were 49.5 mL (standard deviation [SD] 31.1 mL, interquartile range [IQR] 30.2) and 5.4 mL (SD 9.6, mL IQR 5.1), respectively, with an average evacuation rate of 88.7%. All cause 30-d mortality was 8.9%. CONCLUSION: As experience builds with endoscopic minimally invasive ICH evacuation, academic discussion of specific surgical techniques will be critical to maximizing its safety and efficacy.

Long-term functional outcome following minimally invasive endoscopic intracerebral hemorrhage evacuation.

BACKGROUND AND PURPOSE: Preclinical studies suggest that clot removal may mitigate primary and secondary brain injury following intracerebral hemorrhage (ICH). Although the MISTIE trial did not demonstrate an overall outcome benefit, it did demonstrate outcome benefit from effective reduction of clot burden. Minimally invasive endoscopic ICH evacuation may provide an alternative option for clot evacuation. METHODS: Patients presenting to a single healthcare system from December 2015 to October 2018 with supratentorial spontaneous ICH were evaluated for minimally invasive endoscopic evacuation. Inclusion and exclusion criteria were prospectively established by a multidisciplinary group in the healthcare system. The prespecified primary analysis was the proportion of patients with modified Rankin Score (mRS) 0-3 at 6 months. RESULTS: One hundred patients met the inclusion and exclusion criteria and underwent minimally invasive endoscopic ICH evacuation. The mean (SD) hematoma size was 49.7 (30.6) mL, the mean (SD) evacuation percentage was 88.2 (20.3)%, and 86% of patients had postoperative residual hematoma ≤15 mL. At 6 months the proportion of patients with an mRS of 0-3 was 46%. CONCLUSIONS: This study suggests that minimally invasive endoscopic ICH evacuation may produce favorable long-term functional outcomes. Further evaluation of this technique in a randomized clinical trial is necessary.

Pre-hospital detection of acute ischemic stroke secondary to emergent large vessel occlusion: lessons learned from electrocardiogram and acute myocardial infarction.

Currently, there is no device capable of detecting acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO) in the pre-hospital setting. The inability to reliably identify patients that would benefit from primary treatment with endovascular thrombectomy remains an important limitation to optimizing emergency medical services (EMS) triage models and time-to-treatment. Several clinical grading scales that rely solely on clinical examination have been proposed and have demonstrated only moderate predictive ability for ELVO. Consequently, a technology capable of detecting ELVO in the pre-hospital setting would be of great benefit. An analogous scenario existed decades ago, in which pre-hospital detection of acute myocardial infarction (AMI) was unreliable until the emergence of the 12-lead ECG and its adoption by EMS providers. This review details the implementation of pre-hospital ECG (PHECG) for the detection of AMI and explores how early experience with PHECG may be applied to ELVO detection devices, once they become available.

Intracavitary ultrasound (ICARUS): a neuroendoscopic adaptation of intravascular ultrasound for intracerebral hemorrhage evacuation.

Neurosurgeons performing intracerebral hemorrhage evacuation procedures have limited options for monitoring hematoma evacuation and assessing residual hematoma burden intraoperatively. Here, we report the successful neuroendoscopic adaptation of intravascular ultrasound, referred to here as intracavitary ultrasound (ICARUS), in two patients. Pre-evacuation ICARUS demonstrated dense hematomas in both patients. Post-evacuation ICARUS in patient 1 demonstrated significant reduction in clot burden and two focal hyperechoic regions consistent with pockets of hematoma not previously seen with the endoscope or burr hole ultrasound. These areas were directly targeted and resected with the endoscope and suction device. Post-evacuation ICARUS in patient 2 showed significant reduction of hematoma volume without indication of residual blood. ICARUS findings were confirmed on intraoperative DynaCT and postoperative CT 24 hours later. ICARUS is feasibly performed in a hematoma cavity both before and after hematoma aspiration. ICARUS may provide additional information to the operating surgeon and assist in maximizing hematoma removal.

A review of acute ischemic stroke triage protocol evidence: a context for discussion.

Endovascular thrombectomy (EVT) is now the standard of care for eligible patients with acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO). However, there remains uncertainty in how hospital systems can most efficiently route patients with suspected ELVO for EVT treatment. Given the relative geographic distribution of centers with and without endovascular capabilities, the value of prehospital triage directly to centers with the ability to provide EVT remains debated. While there are no randomized trial data available to date, there is substantial evidence in the literature that may offer guidance on the subject. In this review we examine the available data in the context of improving the existing AIS triage systems and discuss how prehospital triage directly to endovascular-capable centers may confer clinical benefits for patients with suspected ELVO.

A review and comparison of three neuronavigation systems for minimally invasive intracerebral hemorrhage evacuation.

Advances in stereotactic navigation technology have helped to improve the ease, reliability, and workflow of neurosurgical intraoperative navigation. These advances have also allowed novel, minimally invasive neurosurgical techniques to emerge. Minimally invasive techniques for intracerebral hemorrhage (ICH) evacuation, including endoscopic evacuation and passive catheter drainage, are notable examples, and as these gain support in the literature and their use expands, stereotactic navigation will take on an increasingly important and central role. Each neurosurgical navigation system has unique characteristics. Operators may find that certain aspects are more important than others, depending on the environment in which the evacuation is performed and operator preferences. This review will describe the characteristics of three popular stereotactic neuronavigation systems and compare their advantages and disadvantages as they relate to minimally invasive ICH evacuation.

The Stereotactic Intracerebral Hemorrhage Underwater Blood Aspiration (SCUBA) technique for minimally invasive endoscopic intracerebral hemorrhage evacuation.

BACKGROUND: Endoscopic intracerebral hemorrhage (ICH) evacuation techniques have gained interest as a potential therapeutic option. However, the instrumentation and techniques employed are still being refined to optimize hemostasis and evacuation efficiency. OBJECTIVE: We describe the application of a specific endoscopic technique in the treatment of ICH called the Stereotactic Intracerebral Hemorrhage Underwater Blood Aspiration (SCUBA) technique. It differs from previously described minimally invasive ICH interventions in that it combines two separate neuroendoscopic strategies in two phases, the first under dry-field conditions and the second using a wet-field strategy. METHODS: All patients who underwent endoscopic ICH evacuation with the SCUBA technique from December 2015 to September 2017 were included. RESULTS: The SCUBA technique was performed in 47 patients. The average evacuation percentage was 88.2% (SD 20.8). Active bleeding identified to derive from a specific source was observed in 23 (48.9%) cases. Active bleeding was addressed with irrigation alone in five cases (10.6%) and required electrocautery in 18 cases (38.3%). Intraoperative bleeding occurred in 3 patients (6.4%) and postoperative bleeding occurred in a single case (2.1%). CONCLUSIONS: The SCUBA technique provides surgeons with a defined strategy for true endoscopic hematoma evacuation. In particular, the fluid-filled cavity in SCUBA Phase 2 has the potential to provide several advantages over the traditional air-filled strategy, including clear identification and cauterization of bleeding vessels and visualization of residual clot burden. Further investigation is necessary to compare this technique to others that are currently used.